1. Field of the Invention
The invention relates to a display device having a pixel electrode formed by a droplet discharge method typified by an ink-jet method, and a manufacturing method thereof.
2. Description of the Related Art
A so-called active matrix drive display panel including a semiconductor element typified by a thin film transistor (hereinafter also referred to as a “TFT”) over a glass substrate is manufactured by patterning according to a light exposure step using a photomask (hereinafter referred to as a photolithography step) and etching various thin films.
In the photolithography step, a resist pattern is formed by coating an entire surface of a substrate with a resist, prebaking, irradiating with ultraviolet light or the like with a photomask therebetween, and then developing. Thereafter, a film pattern of a semiconductor region, an electrode, a wiring, or the like is formed by etching and removing a thin film (a film formed of a semiconductor material, an insulating material, or a conductive material) in a portion not to be a film pattern using the resist pattern as a mask pattern to form a semiconductor element.
Reference 1 discloses a technique for forming a film over a semiconductor wafer by using an apparatus which can continuously discharge a resist from a nozzle to be a linear shape with a fine diameter in order to reduce the loss of a material required for film formation (Reference 1: Japanese Patent Laid-Open No. 2000-188251).
However, since a resist that is a material of a mask pattern is applied to a substrate using a spin coating method in a conventional step of forming a film pattern using a photolithography step, there is a problem of wasting most of a resist material as well as reducing throughput due to a number of steps of forming a mask pattern.
A light exposure apparatus used for the photolithography step has difficulty in performing light exposure treatment on a large-sized substrate at a time. Therefore, a method for manufacturing an active matrix substrate of a display device using a large-sized substrate has a problem of needing to perform light exposure plural times and generating unconformity among adjacent patterns, thereby reducing yield.